It is known to make use of a dosing or metering system for metering predetermined quantities of a sterilizing liquid, e.g. hydrogen peroxide, to spray nozzles for atomizing the liquid in entrainment with a carrier gas and directing the liquid onto or into container parts or containers which must be sterilized before they are used to receive the packaged goods, e.g. comestibles.
Such systems are closely associated with packaging machinery and are capable of effecting a noncontaminating sterilization of the packaging just before the packaging is to receive the goods. The packagings may be, for example, cups adapted to receive dairy products and covers or lids which can be applied to the cups.
A dosing device for the purposes described is illustrated, for example, in German Patent No. 35 40 161.
In the system of that patent, the sterilizing agent is atomized and dispersed in a mixture with compressed air, the resulting mixture has turbulence imparted to it and is evaporated by heating as the sterilizing fluid is sprayed on the surfaces of the packaging material or packaging containers to be sterilized by means of the atomizing blower arrangement.
The supply vessel for the sterilizing agent in this system is located above the transport path of the packaging containers or the packaging material.
This has the significant disadvantage under certain operating circumstances that the machine may become functionally unreliable. For example, especially when the machine is brought to standstill and electric current and compressed air supplies to the machine fail, nonsealing nozzles, leaking valves and screw junctions can permit an uncontrolled flow of the sterilizing agent to the atomizing blower device and result in an accumulation and leakage of the sterilizing agent. Not only does an undesirable loss of the sterilizing agent occur, but excessive accumulations of the sterilizing agent in the packaging containers or on the packaging materials may create unsanitary conditions which must be cleaned up at considerable cost and often with losses of the packaging material.